Sand and gas separator



Nov. 15, 1966 E. TRACY ETAL SAND AND GAS SEPARATOR 2 Sheets-Sheet 1Filed April 26, 1965 Nov. 15, 1966 H. E. TRACY ETAL 3,285,186

SAND AND GAS SEPARATOR Filed April 26, 1965 2 Sheets-Sheet 2 UnitedStates Patent 3,285,186 SAND AND GAS SEPARATOR Herbert E. Tracy,Alhambra, and Theodore D. Matula, Fresno, Califi, assignors toBorg-Warner Corporation, Chicago, Ill., a corporation of Illinois FiledApr. 26, 1965, Ser. No. 450,588 14 Claims. (Cl. 103-113) This inventionrelates to a sand and gas separator for use in combination with a pumpfor pumping water from wells.

The usual form of pump for pumping water from water wells comprises aplurality of vertically stacked stages, each having an impeller mountedfor rotation on a common shaft and driven by a common motor. The pump ispreferably inserted near the bottom of the well and water, entering thefirst stage, is discharged into the next succeeding stage, etc., untilthe water reaches the desired pressure where it is discharged into asuitable pipe for flow to the surface of the earth for consumption.

A common problem in pumping water out of water wells by the aforesaidform of pump has been the presence of sand and gas in the water whichinterferes with the operation of the pump. Sand entering the inlet ofthe pump has acted as an abrasive in the pumping stages, causing damageto the impellers and other parts such as to the shaft and its bearings.This, of course, reduces the life of the pump causing frequent repairand down time. Gas, on the other hand, entering the inlet to the pumphas reduced the efficiency of the impellers which are designed to pumpliquids and, as a result, the amount of water pumped is below the pumpscapacity.

Numerous attempts have been made heretofore to remove the sand and gasfrom the water being pumped by the use of sand and gas separators, butthese attempts have been largely unsatisfactory. Some separators eitherhave themselves contributed to the inefficiency of the pump impellers byreducing the pressure at the inlet to the pump due to internal frictionlosses and the like, or have been unable to remove a sufiicient amountof sand and gas from the water to overcome the aforesaid wear and lossof efficiency problems. Other separators, in addition to their inabilityto remove enough sand and gas, have been unable to rid themselves of thesand and gas removed from the water, and have thus allowed sand and gasto accumulate within the separator which eventually rendered theseparator inoperative. To remove the sand, of course, required the pumpto be withdrawn from the well, and to clear the gas out of the separatorrequired the pump to be stopped until the gas dissipated. Too, theaccumulation of gas within the separator, if not enough to requirestoppage of the pump, still reduced the efiiciency of the separator withthe result that the water entering the pump contained more gas thancould have otherwise been removed.

One of the reasons for the accumulation of sand and gas in theseparators has been the lack of provision in the separators for copingwith the problem caused by the pressure differential existing betweenthe higher pressure water in the well and the lower pressure of the sandand gas laden water within the separators which prevents the flow ofsand and gas out of the separator and back into the well water.

The sand and gas separator which comprises this invention and whichsolves the aforesaid problems comprises a tubular housing connected tothe inlet of the first stage of the pump and provided with means in theform of internal vanes within the housing to spin and induce a vortex inthe sand and gas ladened water entering the housing. This vortex causesthe heavy sand laden water to move toward and follow the inner wall ofthe tubular housing, while a lighter gas laden water is caused to moveice toward the center of the vortex. This lighter gas laden water isremoved by a pickup, located in the housing in the path of the center ofthe vortex, and is connected to a jet pump which reduces the pressure inthe pickup below the pressure of the gas laden water within the vortexso that the gas laden water will flow through the pickup and back to thewater in the well. The sand laden water following the housing wall isdischarged into sand collector chambers which terminate the spinningaction of the sand laden water from whence it is conveyed via tubes to adischarge tube where it is discharged back into the well below theintake of the separator. Inasmuch as the sand laden water will tend toaccumulate and clog the tubes and the collector chambers, a second jetpump is provided so as to induce a continual flow from the collectorchambers through the tubes and out into the well.

Thus, it is a principal object of this invention to provide a new andimproved sand and gas separator for effective removal of sand and gasfrom water being pumped from a well, thus eliminating the damage thatsand can do to the working parts of the pump and eliminating theefficiency loss due to gas entering the pump.

Still another object of this invention is to provide a sand and gasseparator which includes a means for inducing a spin to the sand and gasladen water so as to separate both the sand and the gas from the waterbefore it enters the inlet of the pump and to provide means foreflicient removal of the sand and gas from the separator so as tomaintain the separator operation at a high efficiency level.

Still another object of this invention is to provide a sand and gasseparator with jet pumps so as to provide effective removal of theseparated sand and gas from the separator notwithstanding a lowerpressure level in the separator and the higher pressure level of thewell water.

Other advantages and features'of the present invention will becomeapparent from a more detailed description of the drawings, wherein:

FIGURE 1 is an elevational view of the pump and sand separator as shownlocated in a well;

FIGURE 2 is an enlarge-d cross-sectional, elevational view showing thesand collector chambers located in the separator;

FIGURE 3 is a cross-sectional view taken along line 33 of FIGURE 2;

FIGURE 4 is an enlarged view of a portion of FIG- URE 1 to show the topof the sand discharge tube in more detail;

FIGURE 5 is an enlarged cross-sectional, elevational view showing thepickup for the removal of the gas laden water from within the separator;

FIGURE 6 is an elevational view of the discharge of the pickup;

FIGURE 7 is a plan view of one of the blades used in the separator asvanes to induce the spin to the water traveling therethroug'h, butbefore the blade is twisted to form the vanes; and

FIGURE 8 is a partial view showing one of the vanes located within theseparator housing.

In FIGURE 1, it can be seen that the sand and gas separator 10constructed in accordance with the teachings of this invention islocated below the last stage 12 of the pump 14. Stage 12 comprises animpeller 16 mounted on a shaft 18 and driven by motor 20 so as to rotatein pump bowl 22. The last stage 12 is connected to a pump inlet adaptor24 having internal vanes 26 to direct water entering the pump inlet 30into the impeller inlet 32 where it is discharged out into passages 34of the bowl and into the inlet of the next succeeding impeller, etc.,until the desired pump discharge pressure level is reached.

Sand and gas separator 10 comprises a hollow tubular housing 40 ofsubstantially the same diameter as the pump stages 12 in axial alignmentwith the pump axis. One end of the tubular housing is connected to theinlet adaptor housing 24 in any suitable manner as by threads 42 so asto be suspended from the pump. The tubular housing 40 has a separatorinlet 44 at the end of the tubular housing opposite the pump inlet andinlet 44 is covered with a strainer 46 to prevent large particlesentering the separator inlet.

The separator housing 40 is also provided with a plurality of internalvanes 48 spaced at intervals within the tubular housing so as to causethe fluid flowing from the separator inlet 44 to the pump inlet 30 tospin and form a vortex therein. Vanes 48 are formed, in this embodiment,by twisting flat blades 50, one of which is shown in FIGURE 6, so thateach vane of each blade is inclined with respect to one another andfitted in any suitable manner within the tubular housing such as bywelding 52 clearly shown in FIGURE 7. All vanes are inclined in the samedirection to induce the spin into the water although the blade axes arelocated at 90 from one another throughout the separator housing toinduce the aforesaid spin on the water.

Located downstream of the vanes, that is, at at point above the vanes asshown in FIGURES 1 and of the drawings, is a pickup 54 with it diverginginlet 56 facing downwardly toward the vanes and separator inlet, andcoaxially of the center of the-vortex so as to pickup the gas ladenwater and gas at the center of the vortex where it will be conveyed byhorizontal pipe or tube 58 into a vertical chamber 60 located on theouts de of the tubular housing. Chamber 60 diverges at its lower end toform a downwardly directed discharge opening 62 for the flow of the gasand gas laden water from pipe 58 past protecting vanes 63 and out intothe well. The protecting vanes 63 are for the purpose of protecting thechamber 60 when the separator is lowered in the well such as to aposition shown in FIGURE 1.

The upper end of chamber 60 is closed and narrower than the dischargeend of the chamber, but extends past the discharge port 64 of the tube58 and is provided with a nozzle 66 located within the chamber and inclose proximity to the discharge 64 so as to form a jet pump 68 withinthe chamber 60. Nozzle 66 is, in turn, in open communication with a zoneof high pressure liquid such as to the high pressure side of stage 12 bya tube 70 so as to convey high pressure liquid to the nozzle 66 tocreate a zone of low pressure at the discharge 64 and in accordance withthe principle of operation of the jet pumps. This low pressure 'zonecreates a flow from the mouth 56 of the pickup, thus creating a lowpressure zone within the mouth 56 to pickup the gas and gas laden waterin the center of the Vortex and cause a continual flow thereof from thepickup 54 to the discharge opening 62 of the chamber.

As hereinbefore mentioned, under certain conditions the pressure of thegas laden water, etc., in the center of the vortex may be lower than thepressure of the water in the well due to friction losse in the separatorand due to inherent function of the vortex, and thus the gas laden waterwould not flow out of the separator. However, this problem is solved byuse of the aforesaid jet pump 68 which creates a zone of low pressure atthe discharge 64 of the pipe 58, which low pressure is maintained lowerthan the low pressure in the mouth of the pickup so that there is acontinual flow past the discharge 60 where it is directed by the jetfrom the pump out of the separator and back into the Well. This preventsthe accumulation of gas within the separator and increases itsefliciency and prevents gas from entering the pump inlet 30.

Referring again to FIGURE 1, and also to FIGURES 2-4, inclusive, it willbe seen that the tubular housing 40 is also provided with a pair ofopenings 80 almost diametrically opposite to one another and locatedbelow a conically-shaped baflle 86, both of which are located below thepump inlet 30. The openings 80 communicate with a pair of sand collectorchambers 82 and 84 located on the outside of the tubular housing so thatthe sand laden water traveling upwards on the inside of the tubularhousing will flow into these sand collector chambers. Openings '80 havesharp, vertical edges 88 to prevent the formation of eddies in thespinning sand laden water as the latter passes through the openings andthe bafile 86, located immediately above the openings, obstructs thetravel of any sand laden water past the openings to prevent sand fromentering the pump inlet 30.

Sand collector chambers 82 and 84, being semi-annular, extendsubstantially around the outer periphery of the tubular housing and areclosed at their respective top and sides and provided with an aperturedbottom 90 to collect the sand laden water after the latter has passedthrough the openings 80. Chambers 82 and 84 reduce the velocity of thesand laden water and allow the same to settle toward the bottoms 90 ofthe chambers. The apertures 92 (four shown in FIGURE 3) in the bottoms90 form the discharge from the chambers and are connected by a pluralityof tubes 94 which extend downwardly on the outside of the housing andconverge within a discharge pipe 96. Discharge pipe 96 is closed at itstop as at 98 and extends downwardly a distance below a separator inlet44 a sufiicient distance not to disturb the flow of Water into theseparator inlet 44 and is open at its bottom as at 100 to discharge thesand laden water back into the well. It should be noted too that wherethe tubes 94 converge toward the discharge pipe, wires 102 are aflixedthereto so as to form the strainer 46 for the separator inlet.

As hereinbefore mentioned, in prior separators there has been a tendencyfor sand to accumulate and to clog these separators. One of the reasonsfor this is that prior separators were unable to cope with the pressuredifferential between the pressure of the water in the well and thepressure within the separator which was almost always less than thepressure in the Well. As a result, the prior separators could not ridthemselves of this sand. Too, unless the sand could be kept in motion,there is a natural tendency for it to clog the inner parts of theseparators. This accumulation and clogging of this sand is prevented inthis invention by providing a source of pressure at the discharge end100 of the discharge tube which is lower than the pressure with the sandcollector chambers so that the sand laden water will flow toward thedischarge. This low pressure source is provided by a nozzle 104 locatedwithin the tube 96, but closely ad jacent its end 100 and held in placeby transverse support fins 106, the latter permitting sand and water topass through and out the discharge pipe. This nozzle 104 is connected bytubes 108 to a source of high pressure which, in this case, is the highpressure side of the first stage 12 of the pump so as to direct highpressure water toward the discharge 100 and thus form a jet pump 110 andwhich, in accordance with the principle of this device, creates this lowpressure zone in the discharge pipe 96 so that the sand laden water willcontinually flow toward the discharge and will be directed by the jet ofthe pump back into the well. I

From the foregoing, after the pump and separator are lowered into thewell, as illustrated in FIGURE 1, water containing sand and gas enteringthe separator inlet 44 will travel upwardly toward the pump inlet 30,but during its travel will be induced to form a vortex by the operationof the blades48. The lighter, gas laden water, by the operation of thevortex, will travel toward the center while the heavier sand laden wateris forced to travel upward along the inner walls of the tubular housing.The gas laden water will then be picked up by the pickup 54 and conveyedout into the well by operation of the jet pump 68. The sand laden Waterwill travel further up the tubular housing where it will enter the sandcollector chambers and be conveyed out into the well through thedischarge by the jet pump 110. In the meantime, the sand-gas-free waterwill travel upwardly past the bafiie 86 above the openings 80 where thediagonal vanes 112 Will stop the spin of the water traveling past thebaflle to prevent any adverse eflects on the pump because of spin.

In the above description of this invention, reference has been made tothat which is picked up by the pickup 54 as gas and gas laden water? andgas and gas laden water. These terms were used almost interchangeablyinasmuch as more often than not that which is picked up will be amixture of gas, water having entrained gas and Water, and these term-swere intended to mean that which moves toward the center of the vortexto be carried out to the well water outside the separator.

While only a single embodiment of the present invention is disclosed anddescribed herein, it will be readily apparent to persons skilled in theart that numerous changes and modifications may be made withoutdeparting from the scope of the invention. Accordingly, the foregoingdisclosure and description thereof are for illustrative purposes onlyand do not in any way limit the invention which is defined only by theclaims which follow.

What is claimed is:

1. A device for removing sand and gas from sand and gas laden well waterbefore the latter enters a pump inlet, comprising:

a housing for connecting to the inlet of the pump and for directingwater into the pump inlet, means in said housing for separating thelighter gas laden water from the heavier sand laden water as it flowsthrough the housing toward the pump inlet,

means for removing the gas laden water from the housing and dischargingthe same back under the influence of high pressure Water into the well,and

means for removing the sand laden water from the housing and dischargingthe same back under the influence of high pressure water into the wellso that sand and gas free water will continue to flow on into the pumpinlet.

2. A device for removing sand and gas from water before the latterenters a pump inlet, comprising:

a housing for connecting to the inlet of the pump and for directingwater into the pump inlet, means in said housing for separating thelighter gas laden water from the heavier sand laden water as it flowsthrough the housing toward the pump inlet,

means including a jet pump for removing the gas laden water from thehousing and discharging the same back into the well, and

means including a second jet jump for removing the sand laden water fromthe housing and discharging the same back into the well so that sand andgas free water will continue to flow on into the pump inlet.

3. A device for removing sand and gas from sand and gas laden waterbefore the latter enters a pump inlet, comprising:

a housing for connecting to the inlet of the pump and for directingWater into the pump inlet, means in said housing for separating thelighter gas laden water from the heavier sand laden Water as it flowsthrough the housing toward the pump inlet,

means connected to a source of low pressure outside said housing forremoving the gas laden water from the housing and discharging the sameback into the well, and

means connected to a source of low pressure outside said housing forremoving the sand laden water and discharging the same back into thewell so that sand and gas free water will continue to flow on into thepump inlet.

4. A device for removing sand and gas from sand and gas laden waterbefore the latter enters a pump inlet, comprising:

a. tubular housing for connecting to the inlet of the pump and fordirecting water into the pump inlet, means in said housing forseparating the lighter gas laden water from the heavier sand laden wateras it flows through the housing toward the pump inlet,

means for removing the gas laden water from the housing and dischargingthe same back into the well, said means including a jet pump, and

means for removing the sand laden water and discharg ing the same backinto the well so that sand and gas free water will continue to flow oninto the pump inlet,

said means including apertures in said housing, sand collecting chambermeans communicating with said apertures to collect said sand laden water[flowing into collecting chamber means, a discharge tube, meansconnecting said collector chamber means to said discharge tube, and asecond jet pump in said discharge tube to pump said sand laden Waterfrom said sand collector chamber means.

5. A device for removing sand and gas from sand and gas laden well waterbefore entering a pump inlet, comprising:

a housing for connecting to the inlet of the pump and for directingwater into the pump inlet,

means in said housing for inducing a vortex in the sand and gas ladenwater as it flows through the housing toward the pump inlet by whichlighter gas laden water is transferred to the center of the vortex andheavier sand laden water is transferred to the inner wall of thehousing,

means for removing the gas laden water from the center of the vortex anddischarging the same under the influence of high pressure water backinto the well, and

means for removing the sand laden water and discharging the same underthe influence of high pressure water back into the well so that sand andgas free Water will continue to flow into the pump inlet.

6. A device for removing sand and gas from sand and gas laden well Waterbefore the latter enters a pump inlet, comprising:

a tubular housing for connecting to the inlet of the pump and fordirecting water into the pump inlet, means in said housing for inducinga vortex in the sand and gas laden water as it flows through the tubularhousing toward the pump inlet by which lighter gas laden water istransferred to the center of the vortex and heavier sand laden water istransferred to the inner wall of the housing,

means located at the center of said vortex and connected to a source oflow pressure for removing the gas laden water from the center of thevortex and discharging the same back int-o the well, and

means located at the periphery of the vortex and connected to a sourceof low pressure for removing the sand laden water and discharging thesame back into the well so that sand and gas free water will continue toflow on into the pump inlet.

7. A device for removing sand and gas from sand and gas laden well waterbefore the latter enters a pump inlet, comprising:

a housing for connecting to the inlet of the pump and for directingwater into the pump inlet,

means in said housing for inducing a vortex in the, sand and gas ladenwater as it flows through the housing toward the pump inlet by whichlighter gas laden water is transferred to the center of the vortex andheavier sand laden water is transferred to the inner wall of thehousing,

means including a jet pump for removing the gas laden water from thecenter of the vortex and discharging the same back into the well, and

means including a second jet pump for removing the sand laden water anddischarging the same back into the well so that sand and gas free Waterwill continue to flow on into the pump inlet.

8. A device 'for removing sand and .gas from sand and gas laden waterbefore the latter enters a pump inlet, comprising:

a tubular housing for connecting to the inlet of the pump and fordirecting water into the pump inlet, means in said housing for inducinga vortex in the Water as it flows through the tubular housing toward thepump inlet by which lighter gas laden water transferred to the center ofthe vortex and heavier sand laden water is transferred to the inner wallof the housing,

means for removing gas laden water from the center of the vortex anddischarging the same back into the well, said means including a pickuplocated at the center of the vortex, a jet pump located so as to directthe gas laden water in said pickup to said well, means connecting aidjet pump with said pickup, and

means for removing the sand laden Water and discharging the same backinto the well so that sand and gas free water will continue to flow oninto the pump inlet, said means including sand collector chamber meanslocated so as to receive said sand laden water from said vortex, asecond jet pump located so as to direct said sand laden water in saidcollector chamber means to said well, and means connecting said secondjet pump with said collector chamber means.

9. A device for removing sand and gas from sand and gas laden waterbefore the latter enters a pump inlet, comprising:

a housing for connecting to the inlet of the pump and for directin waterinto the pump inlet,

blade means in said housing for inducing a vertex in the sand and gasladen water as it flows through the housing toward the pump inlet bywhich lighter gas laden water is transferred to the center of the vortexand heavier sand laden water is transferred to the inner wall of thehousing,

means including a jet pump for removing the gas laden water from thecenter of the vortex and discharging the same back into the well,

means including a second jet pump for removing the sand laden water anddischarging the same back into the well so that sand and gas free waterwill continue to flow on into the pump inlet,

baffle means located adjacent said pump inlet to prevent any sand ladenwater from flowing past said means for removing said sand laden water,and

means for stopping the spin of said sand and gas free water as it enterssaid pump inlet.

10. In combination with a submersible pump;

a gas separator unit having a cylindrical housing suspended from thebottom of the pump and forming substantially a coaxial continuationthereof,

said separator housing having an outlet at one end thereof whichconnects to the pump inlet and a separator inlet at its other end, 7

means in said separator housing to induce a vortex in the water enteringthe separator inlet as it moves toward the pump inlet whereby lightergas laden water will move towardthe center of the vortex and heaviersand laden water will move toward the inner wall of the separatorhousing, 1

means for separating the lighter water and discharging the same backinto the well by creating a low pressure zone outside said separatorhousing and causing a flow of said lighter water thereto, and

means for separating out the heavier water and discharging the same backinto the well so that sand and gas free water enters the pump inlet bycreating a second zone of low pressure outside said separator housingand causing a flow of said heavier Water thereto.

11. The combination claimed in claim 10, wherein said second zone of lowpressure is located below said separator inlet so as not to disturb theflow into said separator inlet.

12. In combination with a submersible pump:

a .gas separator unit having a cylindrical housing suspended from thebottom of the pump and forming substantially a coaxial continuationthereof,

said separator housing having an outlet at one end thereof whichconnects to the pump inlet and a separator inlet at its other end,

vane means in said separator housing to induce a vortex in the waterentering the separator inlet as it moves toward the pump in-let where-bylighter gas laden water will move toward the center of the vortex andheavier sand laden water will move toward the inner Wall of theseparator housing,

means for separating the lighter water and discharging the same backinto the well including a pickup to receive the lighter water, and a jetpump connected to said pickup to pump the lighter water in said pickupout said separator housing, and

means for separating out the heavier water and discharging the same backinto the well so that sand and gas free water enters the pump inlet,sand collector chamber means communicating with the inside of saidhousing to receive said heavier Water and a jet pump connected to saidsand collector chamber means to pump the heavier Water in said sandcollector chamber means out said chamber means.

13. in a combination with a submersible pump:

a gas separator unit having a cylindrical housing suspended from thebottom of the pump and forming substantially a coaxial continuationthereof,

said separator housing having an outlet at one end thereof whichconnects to the pump inlet and a separator inlet at its other end,

means in said separator housing to induce a vortex in the water enteringthe separator inlet as it moves toward the pump inlet whereby heaviersand laden water will move toward the inner wall of the separatorhousing, and

means including a jet pump for separating out the heavier water anddischarging the same back into the well.

14. In combination with a submersible pump:

a gas separator unit having a cylindrical housing suspended from thebottom of the pump and forming susbtantially a coaxial continuationthereof,

said separator housing having an outlet at one end thereof whichconnects to the pump inlet and a separator inlet at its other end,

means in said separator housing to induce a vortex 1n the Water enteringthe separator inlet as it moves toward the pump inlet whereby lightergas laden water will move toward the center of the vortex, and

means including a jet pump for separating the lighter Water anddischarging the same back into the well.

References Cited by the Examiner UNITED STATES PATENTS 2,795,873 6/ 1957Hoffman. 2,872,985 2/1959 Bertu-zzi et al 103-203 X 3,106,526 10/1963Schmidt 103-203 X 7 ROBERT M. WALKER, Primary Examiner.

1. A DEVICE FOR REMOVING SAND AND GAS FROM SAND AND GAS LADEN WELL WATERBEFORE THE LATTER ENTERS A PUMP INLET, COMPRISING: A HOUSING FORCONNECTING THE INLET OF THE PUMP AND FOR DIRECTING WATER INTO THE PUMPINLET, MEANS SAID HOUSING FOR SEPARATING THE LIGHTER GAS LADEN WATERFROM THE HEAVIER SAND LADEN WATER AS IT FLOWS THROUGH THE HOUSING TOWARDTHE PUMP INLET, MEANS FOR REMOVING THE GAS LADEN WATER FROM THE HOUSINGAND DISCHARGING THE SAME BACK UNDER THE INFLUENCE OF HIGH PRESSURE WATERINTO THE WELL, AND MEANS FOR REMOVING THE SAND LADEN WATER FROM THEHOUSING AND DISCHARGING THE SAME BACK UNDER THE INFLUENCE OF HIGHPRESSURE WATER INTO THE WELL SO THAT SAND AND GAS FREE WATER WILLCONTINUE TO FLOW ON INTO THE PUMP INLET.